49 research outputs found
Doppler-tuned Bragg Spectroscopy of Excited Levels in He-Like Uranium: a discussion of the uncertainty contributions
We present the uncertainty discussion of a recent experiment performed at the
GSI storage ring ESR for the accurate energy measurement of the He-like uranium
1s2p3P2- 1s2s3S1 intra-shell transition. For this propose we used a Johann-type
Bragg spectrometer that enables to obtain a relative energy measurement between
the He-like uranium transition, about 4.51 keV, and a calibration x-ray source.
As reference, we used the Ka fluorescence lines of zinc and the Li-like uranium
1s22p2P3/2 - 1 s22s 2S1/2 intra-shell transition from fast ions stored in the
ESR. A comparison of the two different references, i.e., stationary and moving
x-ray source, and a discussion of the experimental uncertainties is presented
Doppler-tuned Bragg Spectroscopy of Excited Levels in He-Like Uranium: a discussion of the uncertainty contributions
We present the uncertainty discussion of a recent experiment performed at the
GSI storage ring ESR for the accurate energy measurement of the He-like uranium
1s2p3P2- 1s2s3S1 intra-shell transition. For this propose we used a Johann-type
Bragg spectrometer that enables to obtain a relative energy measurement between
the He-like uranium transition, about 4.51 keV, and a calibration x-ray source.
As reference, we used the Ka fluorescence lines of zinc and the Li-like uranium
1s22p2P3/2 - 1 s22s 2S1/2 intra-shell transition from fast ions stored in the
ESR. A comparison of the two different references, i.e., stationary and moving
x-ray source, and a discussion of the experimental uncertainties is presented
Doppler-tuned Bragg Spectroscopy of Excited Levels in He-Like Uranium: a discussion of the uncertainty contributions
We present the uncertainty discussion of a recent experiment performed at the
GSI storage ring ESR for the accurate energy measurement of the He-like uranium
1s2p3P2- 1s2s3S1 intra-shell transition. For this propose we used a Johann-type
Bragg spectrometer that enables to obtain a relative energy measurement between
the He-like uranium transition, about 4.51 keV, and a calibration x-ray source.
As reference, we used the Ka fluorescence lines of zinc and the Li-like uranium
1s22p2P3/2 - 1 s22s 2S1/2 intra-shell transition from fast ions stored in the
ESR. A comparison of the two different references, i.e., stationary and moving
x-ray source, and a discussion of the experimental uncertainties is presented
Differential energy measurement between He- and Li-like uranium intra-shell transitions
We present the first clear identification and highly accurate measurement of
the intra-shell transition 1s2p\, ^3P_2 \to 1s2s\, ^3S_1 of He-like uranium
performed via X-ray spectroscopy. The present experiment has been conducted at
the gas-jet target of the ESR storage ring in GSI (Darmstadt, Germany) where a
Bragg spectrometer, with a bent germanium crystal, and a Ge(i) detector were
mounted. Using the ESR deceleration capabilities, we performed a differential
measurement between the 1s2p\, ^3P_2 \to 1s2s\, ^3S_1 He-like U transition
energy, at 4510 eV, and the 1s^22p\ ^2P_{3/2} \to 1s^22s\, ^2S_{1/2} Li-like
U transition energy, at 4460 eV. By a proper choice of the ion velocities, the
X-ray energies from the He- and Li-like ions could be measured, in the
laboratory frame, at the same photon energy. This allowed for a drastic
reduction of the experimental systematic uncertainties, principally due to the
Doppler effect, and for a comparison with the theory without the uncertainties
arising from one-photon QED predictions and nuclear size corrections
Observation of the 2p3/2 -> 2s1/2 intra-shell transition in He-like uranium
We present the first observation of the 1s2p 3P2 ? 1s2s 3S1 transition in
He-like uranium. The experiment was performed at the internal gas-jet target of
the ESR storage ring at GSI exploiting a Bragg crystal spectrometer and a
germanium solid state detector. Using the 1s2 2p 2P3/2 ? 1s2 2s 2S1/2
transition in Li-like uranium as reference and the deceleration capabilities of
the ESR storage rings, we obtained the first evaluation of the He-like heavy
ion intra-shell transition energy
Adaptive model-driven user interface development systems
Adaptive user interfaces (UIs) were introduced to address some of the usability problems that plague many software applications. Model-driven engineering formed the basis for most of the systems targeting the development of such UIs. An overview of these systems is presented and a set of criteria is established to evaluate the strengths and shortcomings of the state-of-the-art, which is categorized under architectures, techniques, and tools. A summary of the evaluation is presented in tables that visually illustrate the fulfillment of each criterion by each system. The evaluation identified several gaps in the existing art and highlighted the areas of promising improvement
Healthcare-associated pneumonia in acute care hospitals in European union/European economic area countries: an analysis of data from a point prevalence survey, 2011 to 2012
An aim of the ECDC point prevalence survey (PPS) in European Union/European Economic Area acute care hospitals was to acquire standardised healthcare-associated infections (HAI) data. We analysed one of the most common HAIs in the ECDC PPS, healthcare-associated pneumonia (HAP). Standardised HAI case definitions were provided and countries were advised to recruit nationally representative subsets of hospitals. We calculated 95% confidence intervals (CIs) around prevalence estimates and adjusted for clustering at hospital level. Of 231,459 patients in the survey, 2,902 (1.3%; 95% CI: 1.2–1.3) fulfilled the case definition for a HAP. HAPs were most frequent in intensive care units (8.1%; 95% CI: 7.4–8.9) and among patients intubated on the day of the survey (15%; 95% CI: 14–17; n = 737 with HAP). The most frequently reported microorganism was Pseudomonas aeruginosa (17% of 1,403 isolates), followed by Staphylococcus aureus (12%) and Klebsiella spp. (12%). Antimicrobial resistance was common among isolated microorganisms. The most frequently prescribed antimicrobial group was penicillins, including combinations with beta-lactamase inhibitors. HAPs occur regularly among intubated and non-intubated patients, with marked differences between medical specialities. HAPs remain a priority for preventive interventions, including surveillance. Our data provide a reference for future prevalence of HAPs at various settings